St. Helena endures about 28 more days above 90 °F each year.
The year at a glance
Averages from 30 years of climate history, 1991-2020
| Santa Rosa | Metric | St. Helena |
|---|---|---|
| 258 days | Sunny daysclear or partly cloudy skies | 259 days |
| 30 in | Precipitationper year | 27 in |
| 60 days | Wet daysrain or snow per year | 58 days |
| 0 in | Snowfallper year | 0 in |
| 26 days | Hot daysabove 90 °F | 54 days |
| 15 days | Freezing nightsat or below 32 °F | 14 days |
| 70% | Humidityaverage relative | 66% |
| 59 °F | Average temperatureyear round | 61 °F |
Monthly temperatures
Average daily high and low for each month, in °F. The gap between the two lines is what an ordinary day feels like across the year.
Daily highs
Daily lows
View monthly temperatures as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Santa Rosa high | 60 | 64 | 67 | 71 | 74 | 80 | 82 | 83 | 84 | 79 | 67 | 59 |
| St. Helena high | 59 | 62 | 67 | 72 | 78 | 85 | 89 | 89 | 87 | 78 | 66 | 58 |
| Santa Rosa low | 38 | 40 | 42 | 44 | 48 | 51 | 52 | 53 | 51 | 47 | 42 | 38 |
| St. Helena low | 40 | 42 | 44 | 46 | 51 | 54 | 56 | 56 | 54 | 49 | 44 | 40 |
Monthly precipitation
Total rain plus melted snow for each month, in inches. Taller bars mean wetter months.
View monthly precipitation as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Santa Rosa | 5.7 | 5.9 | 4.4 | 1.9 | 1.1 | 0.3 | 0.0 | 0.0 | 0.1 | 1.3 | 3.0 | 5.9 |
| St. Helena | 5.4 | 5.4 | 4.0 | 1.7 | 1.0 | 0.3 | 0.0 | 0.0 | 0.1 | 1.3 | 2.7 | 5.5 |
Monthly sunny days
Days each month with clear or partly cloudy skies, so compare the same month between cities.
View monthly sunny days as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Santa Rosa | 14 | 13 | 16 | 19 | 23 | 27 | 30 | 30 | 28 | 25 | 18 | 15 |
| St. Helena | 14 | 13 | 16 | 19 | 24 | 27 | 30 | 30 | 28 | 25 | 18 | 15 |
Keep comparing
Nearby cities and popular picks for each side of this matchup. Any two cities can be compared from the home page.
Santa Rosa vs another city
- Santa Rosa vs Larkfield-Wikiup, CA
- Santa Rosa vs Rohnert Park, CA
- Santa Rosa vs Sebastopol, CA
- Santa Rosa vs Cotati, CA
- Santa Rosa vs Windsor, CA
- Santa Rosa vs Calistoga, CA
- Santa Rosa vs New York, NY
- Santa Rosa vs Los Angeles, CA
- Santa Rosa vs Chicago, IL
- Santa Rosa vs Houston, TX
- Santa Rosa vs Phoenix, AZ
- Santa Rosa vs Philadelphia, PA
St. Helena vs another city
- St. Helena vs Calistoga, CA
- St. Helena vs Boyes Hot Springs, CA
- St. Helena vs Sonoma, CA
- St. Helena vs Larkfield-Wikiup, CA
- St. Helena vs Rohnert Park, CA
- St. Helena vs New York, NY
- St. Helena vs Los Angeles, CA
- St. Helena vs Chicago, IL
- St. Helena vs Houston, TX
- St. Helena vs Phoenix, AZ
- St. Helena vs Philadelphia, PA
About this data
Every figure on this page is a 30 year average computed from daily climate history for 1991-2020, using each city's own coordinates. Wet days count days with measurable precipitation, calibrated against the wet day counts in NOAA's published climate normals. Sunny days count clear plus partly cloudy days, defined as average cloud cover of 63 percent or less and calibrated against NOAA's published sky cover tables. Snowfall figures are model estimates anchored to NOAA station measurements near each city.
Weather data by Open-Meteo.com (CC BY 4.0). Contains modified Copernicus Climate Change Service information (ERA5, ERA5-Land).